aftershocks

The Central Weather Administration says the limited number of aftershocks
following Saturday night's magnitude 7 earthquake that struck off the
northeast coast is due to its occurring at a greater depth in a subduction
zone.

The offshore earthquake was centered some 32-kilometers east of Yilan County
Hall offshore, at a depth of 73-kilometers.

Data shows that only three aftershocks have been reported since then.

The first of them occured about an hour-and-a-half after the initial quake
and two more were recorded on Sunday.

The weather administration's Seismological Center says the difference between
the April, 2024 Hualien quake, which was followed by frequent aftershocks,
and this past Saturday's quake off of Yilan is due to the quake's depth and
tectonic setting.

The CWA said Saturday's Yilan quake was caused by the Philippine Sea Plate
subducting northward beneath the Eurasian Plate ..

.. and such deep earthquakes generally generate fewer aftershocks and weaker
surface shaking.

However, the center is warning that aftershocks in the magnitude 5.5 to 6
range are still possible over the coming week.